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101.
102.
Serum samples from 996 dogs in Switzerland were examined for antibodies to Ehrlichia canis and to the agent causing canine granulocytic ehrlichiosis (CGE). Ehrlichiosis, borreliosis, and systemic illness not associated with ticks were suspected in 75, 122, and 157 of these dogs, respectively. The remainder of the serum samples were obtained from clinically healthy dogs which resided north (n = 235) or south (n = 407) of the Alps. The serum samples were tested by an indirect immunofluorescence technique for antibodies to the two agents incriminated, E. canis and Ehrlichia phagocytophila, a surrogate marker of the agent of CGE. Twenty-two of 996 (2.2%) serum samples had antibodies to E. canis and were distributed as follows: 20 of 75 (26.7%) samples from dogs suspected of having ehrlichiosis, 1 of 122 (0.8%) from dogs suspected of having borreliosis, and 1 of 407 (0.2%) from healthy dogs which resided south of the Alps. Of the 75 (7.5%) serum samples that had antibodies to E. phagocytophila, significantly more samples were from ill dogs than from healthy dogs. Among the sera from healthy dogs, antibodies to E. phagocytophila were significantly more prevalent in the north. Because seropositive dogs had a history of travel outside Switzerland and because Rhipicephalus sanguineus is found exclusively south of the Alps, it was presumed that, in contrast to the agent of CGE, E. canis is not indigenous to Switzerland.  相似文献   
103.
A cross-sectional survey in individuals affected with the lysosomal storage disease Mucopolysaccharidosis VI (MPS VI) was conducted to establish demographics, urinary glycosaminoglycan (GAG) levels, and clinical progression of the disease. The survey evaluated 121 bona fide MPS VI-affected individuals over the age of 4 years from 15 countries across the Americas, Europe, and Australasia representing greater than 10% of the estimated world prevalence of the disease. A medical history, complete physical exam, urinary GAG determination, and assessment of several clinical measures related to physical endurance, pulmonary function, joint range of motion, strength, and quality of life were completed for each participant. Although a wide variation in clinical presentation was observed, several general findings were obtained reflecting progression of the disease. Impaired physical endurance, as measured by the distance achieved in a 6-min walk, could be demonstrated across all age groups of MPS VI-affected individuals. High urinary GAG values (>200 mug/mg creatinine) were associated with an accelerated clinical course comprised of age-adjusted short stature and low body weight, impaired endurance, compromised pulmonary function, and reduced joint range of motion. An unexpected result was the predominance of urinary GAG values <100 mug/mg creatinine for those participants over the age of 20 years. Pending the collection of longitudinal data, these results suggest that urinary GAG levels predict clinical morbidity, and longer-term survival is associated with urinary GAG levels below a threshold of 100 mug/mg creatinine.  相似文献   
104.
Aberrant glycosylation is a common feature of metastatic sub-clones of malignant tumours and in uveal melanoma in particular, the HNK-1 glycotope has been positively correlated with poor prognosis. So far, no such correlation has been investigated in cutaneous melanoma. In order to do so, HNK-1 expression was evaluated immunohistochemically in 100 primary cutaneous melanomas and correlated with metastasis after up to 10-years' follow-up. Furthermore, HNK-1 expression was analysed in metastatic deposits (19 distant cutaneous metastases and six sentinel lymph node metastases), as well as in benign nevi. Kaplan-Meier analysis revealed a positive association between HNK-1 expression and metastasis (p < 0.005) and multivariate Cox regression analysis adjusted for the standard prognostic markers ulceration and vertical tumour thickness confirmed HNK-1 expression as an independent prognostic marker. HNK-1 expression was preserved in 42% of the distant cutaneous metastases, but metastatic cells in lymph nodes were devoid of HNK-1 immunoreactivity. None of the benign pigmented lesions exhibited HNK-1 immunoreactivity. Expression of the HNK-1 glycotope in cutaneous malignant melanoma is an independent prognostic marker of metastasis. Differential HNK-1 expression at the metastatic sites implies that its expression is modulated by the surrounding environment. As HNK-1 is also transiently expressed during migration of melanocyte precursor cells derived from the neural crest, recapitulation of this transient expression might occur during metastatic spread of cutaneous malignant melanoma.  相似文献   
105.
106.
A case of acute megakaryocytic leukemia (M7) and one of acute myeloid hemopathy affecting megakaryocytic and erythrocytic cell lineages in infants are reported. Both patients had t(1;22)(p12-p13;q13). This translocation was previously observed in a congenital M7 leukemia. These studies suggest that t(1;22) translocation can be nonrandom in M7.  相似文献   
107.
108.
Neuropeptide Y (NPY) receptors are heterogeneous, consisting of at least two subclasses, Y1 and Y2. We sought evidence for differential expression of NPY receptor subtypes in the rat brain. Tissue was incubated with 125I-peptide YY (PYY) which labels NPY and PYY binding sites. The Y1-selective agonist, p[Pro34]NPY, and the Y2-selective agonist, pNPY 13-36, were used as displacing ligands. Autoradiographic analyses of regional receptor binding demonstrated heterogeneity across brain regions. We conclude that Y1- and Y2-receptors may be independently expressed in the brain. While the predominate NPY/PYY receptor subtype in the brain is Y2, there are also Y1-receptors in some brain regions such as the superficial layers of the parietal cortex.  相似文献   
109.
Female Sprague-Dawley rats were either ovariectomized or sham-operated prior to puberty. As adults, they were maintained on a cholesterol-supplemented diet and subjected to either predictable, controllable shock; unpredictable, uncontrollable shock; or no shock for 30 days (51-min daily sessions). Sham-operated rats had higher plasma cholesterol levels than ovariectomized rats, but neither group showed an effect of stress treatments. For both groups, serum triglyceride and aortic cholesterol levels were lower in stressed than nonstressed rats. Additionally, the ovariectomized rats had higher levels of serum triglycerides than sham-operated controls.  相似文献   
110.
The progressive appearance of [3H]kainic acid binding sites with age has been studied in membrane suspensions prepared from various regions of the rat limbic system, and by autoradiography. Binding sites with fast dissociation rate appeared earlier than binding sites with slow dissociation rate. Scatchard analysis demonstrated apparent receptor heterogeneity for both subclasses. High affinity components were detected in the hippocampus as early as 10 days after birth, but in the amygdala + piriform lobe were found only towards the end of the third week, when animals also respond to parenteral kainic acid, for the first time, with limbic seizures accompanied by metabolic activation of the amygdala. Slice autoradiography revealed distinct labelling of the hippocampal CA3 region by postnatal day 10. A comparison with the ontogenesis of the kainic acid-induced seizure-brain damage syndrome suggests a role of high affinity receptors as mediators of metabolic nerve cell activation by kainic acid. However, this receptor interaction per se does not result in neuronal damage to the vulnerable region of the Ammon's horn, which will only occur at an age when also the amygdala is activated by the neurotoxin.  相似文献   
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